Dan Aykroyd has confirmed that Bill Murray will not star in Ghostbusters 3, and that casting is underway to find four new Ghostbusters.

Speaking to Larry King, Aykroyd revealed that “He’s a good friend, I love him, he just doesn’t want to reprise the role. However, there will be a hole for him. If Billy wants to walk in the door and be in the movie, we will find a place. We need four new ghostbusters. We need four new Columbia students.”

When King asked for plot details, Aykroyd replied that “It’s based upon new research that’s being done in particle physics by the young men and women at Columbia University. Basically there’s research being done that… I can say that the world or our dimension that we live in, our four planes of existence, length, height, width, and time, become threatened by some of the research that is being done. And Ghostbusters – new Ghostbusters – have to come and solve the problem.”